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排序方式: 共有589条查询结果,搜索用时 203 毫秒
51.
52.
Rosangela Oliva Federica Albanese Giacomo Cipriani Francesca Ridi Donatella Giomi Marino Malavolti Lorenza Bernini Antonella Salvini 《Journal of Polymer Research》2014,21(7):1-12
A new family of oligotrehaluronamides was synthesized through the polycondensation of α,α-trehaluronic acid dimethyl ester and different diamines or polyamines. In particular, diamines with different molecular structure (1,n-alkylene diamines, aromatic diamine, and alkyleneoxydiamine) were used in order to modulate the molecular weights and the physical characteristics of the products, such as Tg, hydrophilic or hydrophobic properties, and solubility. α,α-Trehaluronic acid was obtained from a renewable source as α,α-trehalose. The syntheses of oligotrehaluronamides were carried out in different solvents such as ethanol, methanol, THF and DMSO, using triethylamine as catalyst. All the compounds obtained in this study were characterized through FT-IR and NMR spectroscopy. The molecular weights were evaluated by 1H-NMR and in some cases compared with those obtained from ESI-MS spectrometry. Glass transition temperatures and melting points were detected by differential scanning calorimetry. Low molecular weight oligoamides, containing several hydroxyl groups, are water-soluble and could be used in water-based formulations. 相似文献
53.
The electrochemical oxidation of 2-naphthol has been studied by galvanostatic electrolysis, using a range of electrode materials such as lead dioxide, boron-doped diamond (BDD) and Ti-Ru-Sn ternary oxide anodes. The influence of some operating parameters, such as current density, flow-rate and chloride concentration on naphthol oxidation has been investigated in order to find the optimum experimental conditions. Measurements of chemical oxygen demand, HPLC and total organic carbon have been used to follow the oxidation. The experimental data indicate that on PbO2 and BDD, naphthol oxidation takes place by reaction with electrogenerated hydroxyl radicals and is favoured by low current density and high flow-rate. On the contrary, on a Ti-Ru-Sn ternary oxide the mineralisation of naphthol occurs only in the presence of chloride ions that act as redox mediators and COD removal is affected by chloride concentration and is not significantly influenced by the current density and mass-transfer coefficient. From a comparison of the results of the three electrodes it has been found that boron-doped diamond gives a faster oxidation rate and better current efficiency. 相似文献
54.
Naghia Ahmed Dario Ronchi Giacomo Pietro Comi 《International journal of molecular sciences》2015,16(8):18054-18076
Replication and maintenance of mtDNA entirely relies on a set of proteins encoded by the nuclear genome, which include members of the core replicative machinery, proteins involved in the homeostasis of mitochondrial dNTPs pools or deputed to the control of mitochondrial dynamics and morphology. Mutations in their coding genes have been observed in familial and sporadic forms of pediatric and adult-onset clinical phenotypes featuring mtDNA instability. The list of defects involved in these disorders has recently expanded, including mutations in the exo-/endo-nuclease flap-processing proteins MGME1 and DNA2, supporting the notion that an enzymatic DNA repair system actively takes place in mitochondria. The results obtained in the last few years acknowledge the contribution of next-generation sequencing methods in the identification of new disease loci in small groups of patients and even single probands. Although heterogeneous, these genes can be conveniently classified according to the pathway to which they belong. The definition of the molecular and biochemical features of these pathways might be helpful for fundamental knowledge of these disorders, to accelerate genetic diagnosis of patients and the development of rational therapies. In this review, we discuss the molecular findings disclosed in adult patients with muscle pathology hallmarked by mtDNA instability. 相似文献
55.
Giacomo Bonanno 《Artificial Intelligence》2009,173(12-13):1194-1203
56.
Yokoyama Daniel Schulze Bruno Borges Fábio Mc Evoy Giacomo 《The Journal of supercomputing》2019,75(10):7003-7036
The Journal of Supercomputing - The ongoing effort to reach the exascale computing barrier has led to a myriad of research and publications in the topic of alternative energy-efficient... 相似文献
57.
The ocean covers about two-thirds of the earth and has a great effect on the future existence of all human beings. About 37%
of the world’s population lives within 100 km of the ocean. The ocean is generally overlooked as we focus our attention on
land and atmospheric issues; we have not been able to explore the full depths of the ocean and its abundant living and non-living
resources. For example, it is estimated that there are about 2,000 billion tons of manganese nodules on the floor of the Pacific
Ocean near the Hawaiian Islands. We discovered, by using manned submersibles, that a large amount of carbon dioxide comes
from the seafloor and extraordinary groups of organisms live in hydrothermal vent areas. Marine robots including unmanned
surface vehicles and unmanned underwater vehicles can help us better understand marine and other environmental issues, protect
the ocean resources of the earth from pollution, and efficiently utilize them for human welfare. This paper briefly presents
some exemplary models of recent developments in marine robots in different application areas. 相似文献
58.
Giacomo Veneri Pietro PiuFrancesca Rosini Pamela Federighi Antonio FedericoAlessandra Rufa 《Pattern recognition letters》2011,32(13):1588-1593
Eye movement is the simplest and repetitive movement that enables humans to interact with the environment. The common daily activities, such as reading a book or watching television, involve this natural activity, which consists of rapidly shifting our gaze from one region to another. In clinical application, the identification of the main components of eye movement during visual exploration, such as fixations and saccades, is the objective of the analysis of eye movements: however, in patients affected by motor control disorder the identification of fixation is not banal. This work presents a new fixation identification algorithm based on the analysis of variance and covariance: the main idea was to use bivariate statistical analysis to compare variance over x and y to identify fixation. We describe the new algorithm, and we compare it with the common fixations algorithm based on dispersion. To demonstrate the performance of our approach, we tested the algorithm in a group of healthy subjects and patients affected by motor control disorder. 相似文献
59.
Michael Würsch Giacomo Ghezzi Matthias Hert Gerald Reif Harald C. Gall 《Computing》2012,94(11):857-885
The Semantic Web provides a standardized, well-established framework to define and work with ontologies. It is especially apt for machine processing. However, researchers in the field of software evolution have not really taken advantage of that so far. In this paper, we address the potential of representing software evolution knowledge with ontologies and Semantic Web technology, such as Linked Data and automated reasoning. We present Seon, a pyramid of ontologies for software evolution, which describes stakeholders, their activities, artifacts they create, and the relations among all of them. We show the use of evolution-specific ontologies for establishing a shared taxonomy of software analysis services, for defining extensible meta-models, for explicitly describing relationships among artifacts, and for linking data such as code structures, issues (change requests), bugs, and basically any changes made to a system over time. For validation, we discuss three different approaches, which are backed by Seon and enable semantically enriched software evolution analysis. These techniques have been fully implemented as tools and cover software analysis with web services, a natural language query interface for developers, and large-scale software visualization. 相似文献
60.
Giacomo Piccinelli Anthony Finkelstein Tommaso Costa 《Information and Software Technology》2003,45(15):1061-1063
The time and costs involved in connecting the IT systems of two companies impact the actual formation of business relationships. A flexible infrastructure for process management is instrumental for rapid and cost-effective B2B integration. One dimension of flexibility that system integrators identify as critical is node-level interaction. In this paper, we discuss the findings of the Nile project on B2B process integration. In particular, we present the methodology defined in Nile for the semi-automatic reconciliation of node-level incompatibilities. 相似文献